Question: I am going to start some bulbs and seeds inside for the first time. I am confused by the number of different kinds of planting mix. Could you recommend how to select the best mix for bulbs and seeds? When should I begin planting so they will be ready to plant outside in May?
Answer: Most indoor planting mixes will work fine for starting bulbs and seeds inside. Some have fertilizer in the mix and some have extra ingredients to give the mix greater water holding capacity. These mixes have advantages for hanging baskets and tubs. However there is no need to pay extra for them when starting seeds and bulbs because they will be planted in the mix a relatively short time.
My favorite mix for seed and bulb starting is half sphagnum peat moss and half vermiculite. Some full service nurseries and garden stores sell this mixture or a similar mixture also containing perlite. It is very easy to buy the two ingredients separately and mix them yourself. Both ingredients are usually quite dry and water must be added while mixing to get the right moisture consistency. The final mix should be damp like a wrung-out sponge, not soaked or soggy.
If you are a first timer, I would recommend starting no more than three or four kinds of seeds and a couple of bulbs until you have more experience. You are committing yourself to regular daily attention for several months.
Unless you have a south facing window or a greenhouse you will need some plant growing lights. LED plant lights are available online starting at about $25. I would also recommend a heating mat to raise the soil temperature for faster seed germination.
Schedules for when to plant various seeds and bulbs are available from some full-service garden stores, from seed catalogs and from online sources.
You can calculate the approximate planting time for specific varieties by determining two factors. First determine the correct time for outdoor planting. The end of May is usually safe for most plants. Some hardy vegetables and flowers can be planted outside as much as a month to six weeks earlier.
Next is to determine about how long it takes to grow a plant from seed to transplanting size. Some fast growing plants like sunflowers and squash only require three to four weeks. Slower growing plants like petunias and begonias may need 12 weeks or longer. Most bulbs need about six to eight weeks. You can find this information for specific plants in books, catalogs and online.